The challenge of treating hyperopia

Although options exist, they are not nearly as numerous as treatments for myopia

Hyperopes present a unique set of challenges for refractive surgeons—most excimer lasers "do a great job with hyperopia with or without astigmatism, as long as you're not steepening the cornea more than about +3.00 diopters, and that last part is a bit laser-specific," said Daniel S. Durrie, M.D., professor of ophthalmology, University of Kansas Medical Center, and president, Durrie Vision, Overland Park, Kan.
The typical hyperope who wants laser vision corrective surgery is "in his early 50s and is presbyopic," said Richard L. Lindstrom, M.D., adjunct professor emeritus, ophthalmology department, University of Minnesota, Minneapolis, and founder, Minnesota Eye Consultants, Minneapolis. Compared with the typical myope, who is about 35 years old, "the management of the two are very different," Dr. Lindstrom said. "The hyperopes typically have great vision until their 40s. By the time they've hit their 50s, they have lousy distance, lousy intermediate, and lousy near vision."
In Europe, Diego de Ortueta, M.D., senior consultant, Augenzentrum Recklinghausen, Germany, said the limits for hyperopic laser treatment are 6.5 D, but the limit "is also given by the post-operative K reading, which will be higher. To avoid inducing aberrations, the post-operative K reading should not be higher than 49 diopters."

Treatment options

Once patients fall into the +7-10 D range, "it's not a good idea to use a corneal procedure because the corneal optics will not be adequate afterward," Dr. Durrie said. A lens-based procedure in hyperopes does not carry the risk of retinal detachment as it would in a high myope and allows surgeons to replace the lens with any corrective power deemed necessary. For patients in their mid-50s, the issues of presbyopia and nuclear sclerosis are also present and lens-based surgery makes sense, he said. Surgeons are not nearly as unanimous when patients are in their mid-40s, however. A +7 D 25-year-old patient? "There's not a lot of surgeons who will replace a lens in that patient scenario," Dr. Durrie said. While not a common procedure, in his practice some higher hyperopic patients in their 20s or 30s are undergoing refractive lens exchange "with excellent results."
Dr. Lindstrom said one reason he rarely performs surgery on those who are +3 D or higher is that "only 65% get to 20/20. Laser surgery induces more higher-order aberrations." Laser surgery just "doesn't generate as high quality vision as we'd like in this group of patients." He prefers monovision or lens-based solutions as well, and added in his hands presbyLASIK "has been disappointing."
"It's a double-edged sword," he said. "These patients don't see well at any distance, so arguably you have more benefit to give them. But it's hard to make them 'perfect.'"
Dr. de Ortueta added, "Phakic lenses are usually not indicated for hyperopic correction as the anterior chamber is too small." His hesitancy with lens-based solutions is the loss of accommodation in younger patients. Dr. Durrie said phakic IOLs also increase the incidence of glaucoma and cataract. Dr. Durrie advised against a partial laser correction. "It's been tried worldwide—just do a three diopter correction and the +7 D 20-year-olds will be happy because they can still accommodate. They're not. And now you've made their cornea significantly steeper. The optics won't be as good for IOL surgery down the road," he said. Because of those earlier disappointments, Dr. Durrie said when he's faced with +7 D 20- (or 30-) year-olds, "I would do everything possible to keep them in contact lenses for now. I think that's better than giving them bad optics and still having to do IOLs down the road." Partial correction "comes back to haunt you later on," because the IOL calculation is so much more difficult, he said. Although Dr. Durrie advises most young hyperopes to wait as long as possible before having surgery, he agreed, "The IOLs we have today—the Crystalens (Bausch + Lomb, Rochester, N.Y.), the ReSTOR +3 (Alcon, Fort Worth, Texas)—those lenses are much better than wearing +7 glasses."
Outside the U.S., corneal inlays are also a potential treatment. For younger hyperopes in the U.S., however, Dr. Lindstrom counsels them about future presbyopia and will suggest either blended or monovision LASIK.

Patient satisfaction

Ideally, patients between +2.00 D and +5.00 D "are the best ones to correct," Dr. de Ortueta said. "They'll get the most benefit of being able to see without spectacle use."
Without a doubt, "this group of people are some of the happiest patients in our whole practice," Dr. Durrie said. "Hyperopes are very grateful," Dr. de Ortueta said. "But we do need to be careful with their near vision. We are inducing negative spherical aberrations, which can give more depth of focus so the near vision is better, but as the patients age, they will need spectacles for near vision."
In a global survey of patient satisfaction with LASIK, Dr. Lindstrom noted satisfaction rates for hyperopes were equivalent to myopes—at about 95%.
"Maybe it's because they're a little older or maybe it's because they have so much more to gain," he said.

Editors' note: Dr. de Ortueta has financial interests with Schwind eye-tech solutions (Kleinostheim, Germany). Dr. Durrie has financial interests with Alcon and Abbott Medical Optics (Santa Ana, Calif.). Dr. Lindstrom is a consultant to industry.

Contact information

De Ortueta: 49 2361 3069770, diego.de.ortueta@augenzentrum.org
Durrie: 913-491-3330, ddurrie@durrievision.com
Lindstrom: 952-888-5800, rllindstrom@mneye.com